package com.example.blog.utils;

import com.example.blog.contant.Contants;
import io.jsonwebtoken.Claims;
import io.jsonwebtoken.JwtParser;
import io.jsonwebtoken.Jwts;
import io.jsonwebtoken.io.Decoders;
import io.jsonwebtoken.security.Keys;
import lombok.extern.slf4j.Slf4j;

import java.security.Key;
import java.util.Date;
import java.util.HashMap;
import java.util.Map;
@Slf4j
public class JWTUtils {
    //1小时（毫秒）
    private static final long JWT_EXPIRATION = 60 * 60 *1000;

    private static String secrtStr = "dVnsmy+SIX6pNptQdeclDSJ26EMSPEIhvZYKBTTug4k=1";

    private static final Key key = Keys.hmacShaKeyFor(Decoders.BASE64.decode(secrtStr));
    /**
     * 生成token
     */
    public static String genJwtToken(Map<String,Object> claim){

        String token = Jwts.builder()
                .setClaims(claim)
                .setExpiration(new Date(System.currentTimeMillis()+JWT_EXPIRATION))
                .signWith(key)
                .compact();
        return token;
    }
    /**
     *校验token
     * Claim为null 失败
     */
    public static Claims parseToken(String token){

        JwtParser build = Jwts.parserBuilder().setSigningKey(key).build();
        Claims claims = null;
        try {
            claims = build.parseClaimsJws(token).getBody();
        }catch (Exception e){
            log.info("解析token失败,token:"+token);
           return null;
        }
        return claims;
    }

    public static Integer getIdByToken(String token){
        Claims claims = parseToken(token);
        if(claims != null){
         Integer userId = (Integer) claims.get(Contants.TOKEN_ID);
         if(userId>0){
             return userId;
             }
        }
        return null;
    }
}
